1. Field of the Invention
The present invention relates to an image forming apparatus, an image forming method, and a printing apparatus that generate image data by analyzing print data described in PDL (page description language) and the like.
2. Description of the Related Art
The image data generation for printing typically includes: 1) vector image processing for analyzing print data such as Post Script or PDL transmitted from a print driver and the like; and 2) raster image processing such as rotation and color conversion.
When print data described in PDL is input, the image forming apparatus analyzes the print data, and generates and outputs image data of compressed format or raster image data of each page. The image data to be input is expressed as a group of a plural kinds of objects (rendering objects). The objects include graphics, and texts.
After the image processing is performed such as converting colors, compositing and rotating pages as required, an image outputted by the image forming apparatus is transmitted to an image output module, and becomes printable. The page image data immediately before printing is a raster image, which are lined up in a scanning order of the image output module.
In general, in order to reduce the time spent from inputting a PDL image to outputting to the image output module, the image is divided into a plurality of areas, and these areas are processed in parallel to reduce the time spent in the image processing of one page. Japanese Patent Application Laid-Open No. Hei 4-170686 discusses the image forming apparatus for forming an image by dividing a two-dimensional area to be rendered into a plurality of blocks, allocating the divided areas to a plurality of image generating means, and forming the image.
However, the image forming process discussed in Japanese Patent Application Laid-Open No. Hei 4-170686 does not consider the data inside each area in the image forming process. Therefore, even if the same data are present in the areas, the data is processed repeatedly, which leads to taking much time in the image formation.